Engineers who need to pass power and signal wires through the walls of pressure and vacuum chambers usually reach for expensive, off-the-shelf, sealed bulkhead connectors. Though bulkhead connectors are the most readily available option, their expense is not only relatable to the connectors themselves, but the work that must go into the design in order to compensate for their large size. Ultimately, the use of such connectors raises costs and can also cause electrical disturbances within the vacuum chambers. As a better alternative, hermitically sealed, epoxy, feed-throughs are being used due to their inexpensive nature in comparison to bulkhead connectors. Yet, there are disadvantages to this technology as well.
Hermetically sealed, epoxy, feed-throughs are messy and difficult to work with, require special consideration to reduce air bubbles and irregularities in the epoxy during the setting process, also may require lengthy periods of time to set. Outgassing of the epoxy can also cause problems in extremely pure environments. The problem with bulkhead connectors is that they are expensive and brittle. Feed-throughs using epoxy have at least the following limitations: one-time use, brittle, messy and difficult to work with, expensive to produce due to time of setting, extensive outgassing of epoxy chemical considerations for contaminating sterile environments.
Due to the limited options available for chamber feed-throughs a need for an alternative arises.